The invention relates to a male contact having a male contact section formed by bending both sides of a metal plate inward, and a method of manufacturing the same.
The contacts shown in FIG. 6 (see Japanese Patent Application Laid-Open No. H7-192793) and FIG. 7 (see Japanese Patent Application Laid-Open No. H8-162191) are known as conventional male contacts that have male contact sections formed by bending both sides of a metal plate inward.
Shown in FIG. 6(A), male contact 100 comprises a male contact section 101 that contacts a mating terminal (not shown), an electrical wire termination portion 102 connected to an electrical wire (not shown), and a securing portion 103 disposed between the male contact section 101 and the electrical wire termination portion 102 that is attached to a connector housing (not shown). Shown in FIG. 6(B), the male contact section 101 is formed by bending both sides of a stamped metal plate 104 so that joining faces 105 are positioned on an upper side in the approximate center with respect to the direction of width of the metal plate 104. The cross-sectional shape of the male contact section 101 is a substantially oval shape in the direction of width. Upper and lower surfaces of the male contact section 101 form substantially flat contact surfaces 106, 107, respectively, that contact a mating female contact (not shown). Curved sections 108 are formed on the four corners of the cross-sectional plane of the male contact section 101. The radius of the curved sections 108 is substantially equal to the thickness of the metal plate 104.
Shown in FIG. 7(A), male contact 200 comprises a male contact section 201 that contacts a mating terminal (not shown), an electrical wire termination portion 202 connected to an electrical wire (not shown), and a securing portion 203 disposed between the male contact section 201 and electrical wire termination portion 202 that is secured to a connector housing (not shown). Shown in FIG. 7(B), the male contact section 201 is formed by bending one side of a stamped metal plate 204 so that joining faces 205 are positioned at a side portion with respect to the direction of width of the metal plate 204. The cross-sectional shape of the male contact section 201 is a substantially oval shape in the direction of width. Upper and lower surfaces of the male contact section 201 form substantially flat contact surfaces 206, 207, respectively, that contact a mating female contact (not shown). Curved sections 208 are formed on the four corners of the cross-sectional plane of the male contact section 201. The curved sections 208 have a radius that is greater than the thickness of the metal plate 204.
Electrical connectors, such as the male contacts 100, 200 shown in FIGS. 6 and 7, are commonly used in industrial fields, such as the automotive field. In recent years there has been a demand for multi-pole connectors. As a result of this demand for multi-pole connectors, a need has arisen for contacts having male contact sections with a small width, for example 0.64 mm square posts.
When male contact sections are formed with a small width, by bending both sides of a stamped metal plate 104 or one side of a metal plate 204 in the same manner as the male contact sections 101, 201 of the male contacts 100, 200, an insufficient area of contact with the mating female contact (not shown) arises due to the fact that the curved sections 108, 208 formed on the four corners of the cross-sectional plane of the male contact sections 101, 201 have radii substantially equal to the thicknesses of the metal plates 104, 204. If a sufficient area of contact with the mating female contact (not shown) can not be obtained, the contact pressure between the contacts is unstable, resulting in unstable contact.
It is therefore desirable to provide a male contact having a sufficient area for contact with a mating female contact in cases where the width of the male contact section formed by bending both sides of a metal plate inward is small. It is further desirable to develop a method of manufacturing the same.
This and other objects of the present invention are solved by a contact part having an electrical wire termination portion, a metal contact part, and a securing portion disposed between the male contact section and the electrical wire termination portion. The male contact section is formed from a metal plate and has a rectangular cross-sectional shape. Curved sections are formed at corners of the cross-sectional shape that have a radius that is equal to or less than ⅓ of the thickness of the metal plate.
The male contact section is formed by bending both sides of the metal plate inward, and then shaping the cross-sectional shape into a substantially rectangular shape by forging so that the curved sections on the four corners of the cross-sectional plane have a radius that is equal to or less than ⅓ of the thickness of the metal plate.